Volume 22, Issue 1

A new series of chalcones 5a–l were synthesized and evaluated for in vitro antiproliferative activity against human colon cancer cell lines. The synthesis of the key intermediate compounds 3a–d was achieved by tetrakis(triphenylphosphine) palladium(II) mediated Suzuki cross coupling reaction. Chalcone 5a shows superior anticancer activity with IC 50 value of 21.0 μg/mL compared to the IC 50 value of the reference drug doxorubicin at 21.65 μg/mL.

A simple and convenient method for the preparation of 2,4-disubstituted 1,3,5-triazine-nitrolic acids has been developed. The first example of nitrolic acid with Z -configuration was revealed by X-ray crystallographic analysis.

Fast (3 min) pot, atom and step economics (PASE) potassium fluoride catalyzed multicomponent reaction of isatins, malononitrile and 4-hydroxy-6-methyl-2 H -pyran-2-one results in efficient formation of substituted spirooxindole-3,4′-pyrano[4,3- b ]pyrans in 92–96% yields. The developed ‘on-solvent’ approach to the substituted spirooxindole-3,4′-pyrano[4,3- b ]pyrans – the pharmacologically perspective substances with known antiviral, antileishmanial, anticonvulsant and anti-HIV activities – is beneficial from the viewpoint of diversity-oriented large-scale processes and represents fast and environmentally benign synthetic concept for the multicomponent reactions strategy.

Esomeprazole {(S)-5-methoxy-2-[(4-methoxy-3, 5-dimethyl-2-pyridinylmethyl) sulfinyl]-1 H -benzimidazole} is a proton pump inhibitor used as an antiulcer drug. Its R-enantiomer 3 was synthesized with high enantioselectivity by asymmetric oxidation of prochiral sulfide 2 using the oxaziridinium salt 4 . Product 3 , useful as a reference for the quality control of esomeprazole, was characterized by 1 H and 13 C NMR, IR, and HRMS. The enantiomeric excess was determined by HPLC.

A series of 2-[(9 H -fluoren-2-yl)aryl]-1 H -benzo[ d ]imidazoles 11–13 and 2,7-bis[(1 H -benzo[ d ]imidazol-2-yl)aryl]-9 H -fluorenes 14–16 containing different linking aromatic units were synthesized in good yields. Their absorption and fluorescence properties were investigated in solution and in the solid state. Most compounds possess good fluorescence-emitting ability with φ FL values in the region of 0.31–0.99 in solution and display strong blue emission. Structure–optical behavior characteristics and further details of the electronic properties from cyclic voltammetry measurements and theoretical calculations are discussed.

1,3,5-Trisubstituted 2-pyrazolines were synthesized by the reaction of chalcones with hydrazine in hot ethanol. Their structures were elucidated by 1 H NMR, 13 C NMR, IR, MS and elemental analysis. The fluorescence spectra were measured in different organic solvents. The emission wavelength is blue shifted with the increase in solvent polarity.

A fluorescent and colorimetric chemosensor Rh1 for Fe 3+ was synthesized by condensation reaction of rhodamine B hydrochloride and 2-aminothiazole, and its structure was confirmed by NMR, IR, HRMS and crystal data. Upon coordination with Fe 3+ in CH 3 CN-H 2 O (1:1, v/v) solution, the spirolactam of Rh1 is opened, which results in a dramatic enhancement of fluorescence intensity as well as the color change of the solution. Most importantly, other metal ions show no obvious interference with the detection of Fe 3+ . Under the optimum conditions described, the fluorescence intensity is linearly proportional to the concentration of Fe 3+ in the range of 2 μ m ~ 7 μ m . The Job’s plot indicates a 1:1 binding stoichiometry between Rh1 and Fe 3+ . The association constant (Ka) is 2.26 × 10 4 m -1 .

A simple and efficient protocol was established to synthesize thiazolo[3,2- a ][1,3,5]triazin-6-ones via three-component one-pot condensation reaction of readily available thioglycolic acid or ethyl thioglycolate, aldehydes or ketones and dicyandiamide in the presence of ammonium acetate. All of the newly synthesized compounds were characterized by spectroscopic analyses.

Synthesis of new 1,2-dihydro-3 H -pyrazolo[3,4- d ] pyrimidin-3-ones 4–6 starting with ethyl 4-hydroxy-2-methylthio-pyrimidine-5-carboxylate ( 1 ) under classical heating and microwave-induced conditions is reported. The antibacterial activities of the synthesized compounds were evaluated using chloramphenicol and streptomycin as reference drugs.

The hitherto unreported, highly functionalized alkyl 2-(2-hydroxy-1,3-dioxo-2,3-dihydro-1 H -inden-2-yl)-2-(3-oxo-3,4-dihydroquinoxalin-2-yl)acetate derivatives 4 have been synthesized in excellent yields via a one-pot three-component reaction of benzene-1,2-diamines, dialkyl acetylenedicarboxylates, and ninhydrin under mild conditions.